The present invention relates generally to devices for directing cables and, more particularly, to a device for directing underground electrical cables between an underground shielded conduit and an above-ground electrical apparatus, such as a switch or transformer.
Virtually all electric power is transmitted from substations to individual users at relatively high voltages, on the order of 5000 to 1500 volts, and tie switches are used to obtain single phase, low current power for distribution as the familiar 110 or 220 volts for household use from three-phase, high current transmission power. Most residential service takes the form of single phase dual voltage AC obtained from the switch. Due to substantially increased demands for electrical power over the recent past in combination with an increased awareness of natural aesthetics, electrical cables are increasingly being buried underground rather than suspended overhead between supporting poles. This has caused the relocation of many switches and power transformers from their pole-mounted positions to ground-supported installations. Underground cables are typically housed in protective conduits which are buried from three to six feet underground. Currently, with underground electrical transmission lines, switches are disposed on concrete pads and the cables are routed upwardly from beneath the surface into the switch for power transmission into and out of the switch.
To install switches associated with underground electrical cables, ground-level supporting pads, which may be formed of concrete, are provided to support the switch slightly above the surrounding earth. The pads themselves are formed with an appropriate number of openings through which the cables may be routed for connection to the switch disposed on the pad.
A common problem with the installation of switches is the difficulty of routing the generally horizontally extending underground cables through a 90.degree. turn to extend generally vertically into the opening for connection to the switch. Current practice utilizes a series of L-shaped conduits which are installed in a row with their upper openings projecting through the opening formed in the concrete pad. The L-shaped conduits are aligned with a template and an individual cable is routed through each conduit. This installation is very time consuming and when the template is removed, the L-shaped conduits tend to shift out of proper alignment resulting in a poor installation.
While the above discussion focuses on electrical switches and underground electrical cables, the principles involved are applicable with installations of other underground cables which are connected to above ground apparatus, such as transformers, buried telephone cable and switching units and buried cable television cable.